Oh dear. Little over a month into his new, high profile role of executive chairman and Sir Stuart Rose has to issue the profit warning that is likely to be the defining moment of the retail slowdown.

The collapse in both food and general merchandise sales in the past three months is startling - down 4.5 per cent and 6.2 per cent respectively - and despite Sir Stuart’s insistence that the macro enviroment has moved against the retailer, critics will once more question the strategy he has been pursuing.

Experts claim that M&S’s food business is still far too wedded to ready meals and sandwiches, at a time when more customers are buying ingredients and cooking themselves as they think it’s cheaper to do so.

The roll-out of Simply Food is also hurting food sales in M&S’s high street stores and its push for cost cuts from suppliers through ‘Project Genesis’ has damaged some long-standing relationships.

On clothing, critical analysts argue that M&S has got it wrong by trying to take on the discounters such as Primark and provide low entry price products at the same time as more ‘aspirational’ ranges such as Autograph. They have lost market share in formal wear, such as mens' suits and womens' blouses.

M&S is still one of the better placed retailers on the high street and the prospects for some of its weaker rivals are frightening.

Sir Stuart reiterated today that customers have less money in their pockets given record fuel prices and rising energy bills but added that consumer confidence seems to have deteriorated markedly in recent weeks.

He should begin to worry about spirits among M&S’s army of private investors. Sir Stuart faces a re-election vote at next week’s annual general meeting and after today it could prove to be a bruising encounter.

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